Dissolvable nanocellulose sheet

Abstract

The present disclosure provides a dissolvable matrix composition, a liquid precursor formulation, and methods of preparing the same. Disclosed compositions and formulations have may be substantially free of polyvinyl alcohol, among other environmental pollutants. The dissolvable matrix composition can be used for household and industrial applications, including laundry, cleaning, personal care, and agricultural uses. Dissolvable matrix compositions in sheet form can be laundry sheets, in-scent booster sheets, odor neutralizer sheets, fabric softener sheets, all-purpose cleaning sheets, toilet bowl sheets, bathroom cleaner sheets, had soap, dishwashing sheets, or auto dishwash sheets. Thus, the dissolvable matrix composition can function as a carrier for various additives, such as household cleaning and laundry products.

What is claimed is: 
     
         1 . A dissolvable sheet comprising:
 a non-woven web comprising a cellulose substrate, a cellulose derivative, and an active ingredient composition, wherein the dissolvable sheet does not contain polyvinyl alcohol (PVA).   
     
     
         2 . The dissolvable sheet of  claim 1 , wherein the cellulose substrate comprises nanocellulose. 
     
     
         3 . The dissolvable sheet of  claim 1 , wherein the cellulose derivative is hydroxyethyl cellulose (HEC), hydroxypropyl cellulose (HPC), hydroxypropyl methylcellulose (HPMC), methyl cellulose, or carboxymethylcellulose sodium (NaCMC). 
     
     
         4 . The dissolvable sheet of  claim 3 , wherein the cellulose derivative is NaCMC, and wherein the CMC is present in an amount of 1 to 15 wt. % relative to the total weight of the sheet. 
     
     
         5 . The dissolvable sheet of  claim 1 , wherein the active ingredient composition comprises at least one surfactant, an enzyme blend, a starch, a dispersion aid, a fragrance, a preservative, or a combination thereof. 
     
     
         6 . The dissolvable sheet of  claim 5 , wherein the at least one surfactant comprises an anionic surfactant, a cationic surfactant, a nonionic surfactant, or a combination thereof. 
     
     
         7 . The dissolvable sheet of  claim 1 , wherein the dispersion aid comprises glycerin. 
     
     
         8 . The dissolvable sheet of  claim 5 , wherein the enzyme blend comprises at least one protease enzyme, at least one amylase enzyme, at least one pectate lyase enzyme, at least one mannanase enzyme, at least one lipase enzyme, or a combination thereof. 
     
     
         9 . The dissolvable sheet of  claim 1 , wherein the dissolvable sheet comprises:
 25 wt. % to 55 wt. % cellulose   10 wt. % to 45 wt. % of a nonionic surfactant;   1 wt. % to 10 wt. % of an anionic surfactant;   1 wt. % to 15 wt. % of a cellulose derivative;   1 wt. % to 10 wt. % of glycerine;   0.1 wt. % to 8 wt. % of an enzyme blend;   0.5 wt. % to 8 wt. % of a starch;   0.01 wt. % to 0.5 wt. % of a preservative; and   1-20 wt. % water, relative to the total weight of the dissolvable sheet.   
     
     
         10 . The dissolvable sheet of  claim 1 , wherein the active ingredient composition is releasable from the sheet when exposed to water. 
     
     
         11 . The dissolvable sheet of  claim 1 , wherein the sheet has a weight of about 1 gram to 8 grams, wherein the range is inclusive. 
     
     
         12 . The dissolvable sheet of  claim 1 , wherein the sheet has a thickness of about 0.1 to 0.3 millimeters, wherein the range is inclusive. 
     
     
         13 . The dissolvable sheet of  claim 1 , wherein the nanocellulose fiber is naturally derived from softwood, hardwood, soy hulls, wheat straw, bagasse, sugar beet pulp, or a combination thereof. 
     
     
         14 . A liquid formulation comprising nanocellulose, a cellulose derivative, a surfactant, an active ingredient, wherein the liquid formulation does not contain polyvinyl alcohol (PVA). 
     
     
         15 . The liquid formulation of  claim 14 , wherein the cellulose derivative is NaCMC, and wherein NaCMC is present in an amount of 2.5 wt. % to 6 wt. % relative to the total weight of the liquid formulation. 
     
     
         16 . A method of manufacturing a dissolvable sheet comprising:
 (i) mixing a cellulose substrate, a cellulose derivative, and optionally an active ingredient composition together, thereby producing a liquid precursor formulation; and   (ii) drying the liquid precursor formulation, thereby producing a dissolvable matrix composition, wherein the drying step reduces the water content of the liquid precursor formulation by at least 35%.   
     
     
         17 . A method of manufacturing a dissolvable sheet comprising:
 (i) processing the liquid formulation of  claim 14  through a roll coater onto a slip sheet;   (ii) drying the liquid formulation by passing the slip sheet through a heater to form a dried sheet roll; and   (iii) cutting the dried sheet roll into individual dissolvable sheets.   
     
     
         18 . The method of  claim 17 , wherein the heater is a convection oven. 
     
     
         19 . The method of  claim 17 , wherein the slip sheet passes through the heater at a speed of from about 0.5 meters per minute to 1.5 meters per minute. 
     
     
         20 . The method of  claim 17 , wherein the liquid formulation is not heated above 120° F. (49° C.) and the maximum internal temperature of the sheet roll does not exceed 120° F. (49° C.).